I am trying to work with the example combiner iterator through java codeinstead of the jar or shell. My question is how do I pass in theIterator<Value> to the reduce method? Usually I would create a KeyValue Iterator, but this requires an Iterator just over the Value, andthen the key to be passed in separately. The reducer method comes fromthe StatsCombiner class under examples/simple/combiner. What I haveright now:

The Iterator<Value> is the "magic" that Accumulo is doing underneath thehood. The Combiner is a neat construct because it performs this reductionserver-side so that your client code doesn't need to.

When you use a Combiner with a (Batch)Scanner or configured on a table, youspecify what granularity of the Key you want that Combiner to combine(row+colfam or row+colfam+colqual) and then Accumulo gives you all of theValues that are grouped together beneath that collection of Keys.

Setting a SummingCombiner over cf1, you would see in the CombinerIterator<Value> from [1,2,3,4,5,6]. If you set the Combiner with no columndefinition, you would see Iterator<Value>'s over [1,2], [3,4], and then[5,6].

The Iterator<Value> is the "magic" that Accumulo is doing underneath thehood. The Combiner is a neat construct because it performs this reductionserver-side so that your client code doesn't need to.

When you use a Combiner with a (Batch)Scanner or configured on a table, youspecify what granularity of the Key you want that Combiner to combine(row+colfam or row+colfam+colqual) and then Accumulo gives you all of theValues that are grouped together beneath that collection of Keys.

Setting a SummingCombiner over cf1, you would see in the CombinerIterator<Value> from [1,2,3,4,5,6]. If you set the Combiner with no columndefinition, you would see Iterator<Value>'s over [1,2], [3,4], and then[5,6].